In addition to high mitochondrial ROS emission, vitiligo patients have a deficient EAS, with low activity and low gene expression of catalase (CAT), glutathione peroxidase (GPx), and thioredoxin reductase (TrxR) (Laddha et al., 2013; Xie et al., 2016), leading to a chronic OS state (Schallreuter, 2014). The gene discussed is CAT; the disease is vitiligo.